From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 31517385802B; Mon, 8 Aug 2022 14:49:57 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 31517385802B From: "adhemerval.zanella at linaro dot org" To: glibc-bugs@sourceware.org Subject: [Bug build/29456] missing DT_HASH section in shared objects Date: Mon, 08 Aug 2022 14:49:57 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: build X-Bugzilla-Version: 2.36 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: adhemerval.zanella at linaro dot org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: security- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: glibc-bugs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Glibc-bugs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 08 Aug 2022 14:49:57 -0000 https://sourceware.org/bugzilla/show_bug.cgi?id=3D29456 --- Comment #7 from Adhemerval Zanella --- (In reply to Arkadiusz Hiler from comment #5) > (In reply to Florian Weimer from comment #3) > > Distributions configure or patch GCC to pass --hash-style=3Dgnu to the = linker > > by default. The linker default does not matter. >=20 > Thanks, that explains a few things. My gcc -v indeed claims that: >=20 > Configured with: /build/gcc/src/gcc/configure ... > --with-linker-hash-style=3Dgnu ... >=20 > According to gcc/docs/install.texi the default is sysv but after browsing > the code for a bit it looks like if `--with-linker-hash-style` is not > specified no `--hash-style` is passed to the linker so it would depend on > linker's defaults. >=20 > Do you know why distros do this? Looking at package history it seems like= an > artifact from the times where both was a bit problematic. There used to be > some custom patches for that years ago. >=20 >=20 > (In reply to Adhemerval Zanella from comment #4) > > > This breaks all the games running via Proton that are using EAC. > >=20 > > What EAC is doing exactly that requires a DT_HASH on glibc? What happen= s if > > you mix DT_HASH and DT_GNU_HASH shared objects (for instance shared > > libraries with only one option)? It does seem a shortcoming from EAC, > > although I am not sure what exactly it is trying to enforce here. >=20 > I can only guess but probably to look up some symbols in multiple ways to > assure no hooking has occurred. >=20 > It seems to require it only for the glibc DSOs as they were shipping with > DT_HASH for years, even on distros that default to gnu, and this is an > unexpected change. Right, however, I am not sure this characterize as an ABI break since the symbol lookup information would be indeed provided (albeit in a different format). And it should be transparent to most applications as well since sy= mbol resolution is done by the loader itself. --=20 You are receiving this mail because: You are on the CC list for the bug.=